In this preview of the show's June 3 premiere, Kardashian -- who divorced Kris Humphries in October and is now dating Kanye West -- encounters struggling model Stacy (April Bowlby), who still pines for her ex.

Eager to help, Kardashian's Nikki offers a key piece of advice to lovelorn Stacy: Be assertive. "Now is the time to make bold moves," her character suggests. "And don't leave anything on the table. Well, undergarments optional!"

Reality star Kardashian clearly impressed her Drop Dead Diva costars and crew during filming, and the show's creator, Josh Berman, tells Us Weekly his new guest star was a total pro.

"I'm blown away by her smarts, sense of humor, and passion," Berman told Us at the time of Kardashian's casting. "This series is all about reinvention and I'm so excited to see Kim 'reinvented' in the world of Drop Dead Diva."

Watch more of her Drop Dead Diva guest spot in the clip above before Kim Kardashian's first of three episodes airs June 3 at 9 p.m. (EST) on Lifetime.